How to provoke urban interaction? In cities where people are increasingly distant, design can be used to bring people together. Libra is a bench, but also a small seesaw. It wobbles as you sit on it. To use it is to move whoever is there already, possibly sparking a conversation.
An inconvenient design choice in favour of social behaviour.
Libra is made of folded steel. This single ribbon must support the seat, form the hinge and rotation lock, and take loads to the ground. It must also stack vertically, to optimise transportation to site.
How many folds are necessary? How many ribbon combinations satisfy these requirements? A ribbon algorithm was coded, with the ability to transform an initial ribbon into a target position within N folds. A genetic algorithm then iterated through the solution space, eventually reaching the optimum.
A designer is unnecessary in the presence of enough constraints.